Chennai, Nov 3 (IANS): The Regional Meteorological Centre (RMC) has predicted heavy to very heavy rains accompanied by thunderstorms across 12 districts of Tamil Nadu on Sunday.

According to the weather forecast, Chennai, Chengalpattu, Tiruvallur, Kancheepuram, Nilgiris, Coimbatore, Ramanathapuram, Pudukottai, Nagapattinam, Thoothukudi, Tirunelveli, and Kanyakumari districts are expected to experience intense rainfall and thunderstorms on Sunday.

In addition, the RMC has issued a yellow alert for 19 districts in Tamil Nadu, forecasting heavy rains over the next two days. This rainfall is attributed to a cyclonic system and an upper air circulation over the sea.

The districts expected to receive substantial rainfall include Coimbatore, Tiruppur, The Nilgiris, Madurai, Erode, Virudhunagar, Theni, Dindigul, Tenkasi, Tirunelveli, Kanyakumari, Krishnagiri, Ramanathapuram, Dharmapuri, Salem, Namakkal, Karur, Thoothukudi, and Sivaganga.

The RMC has indicated that a cyclonic circulation over the Gulf of Mannar has weakened, although an upper air circulation remains over the southwest Bay of Bengal, near the southern Andhra coast.

Extended-range predictions suggest coastal Tamil Nadu may experience below-normal rainfall, while other areas could see above-average rainfall through November 7.

From November 8 to 14, near-normal to slightly above-normal rainfall is forecast across much of Tamil Nadu. Fishermen have been advised to not venture into the sea for the next 48 hours due to anticipated winds of 35-45 kmph, with gusts reaching up to 55 kmph along the southern Tamil Nadu coast, the Gulf of Mannar, and around the Cameron region.

The Northeast Monsoon, which began on October 17, has already brought substantial rainfall to Tamil Nadu.

The India Meteorological Department (IMD) anticipates normal to above-normal rainfall for northern Tamil Nadu, while southern parts are expected to see normal levels, though several southern districts have already experienced significant rain.

For the October-December period, the IMD expects the southern peninsular region, including Kerala, Tamil Nadu, and Andhra Pradesh, to receive 112 per cent of the long-term average rainfall of 33.4 cm. Tamil Nadu typically receives an average of 44 cm during the northeast monsoon period.